Snow ploughs



United States Patent 3,365,822 SNOW PLOUGHS James Bryson Howie, Woodmancote, near Cheitenham, England, assignor to J. B. Howie Limited, Birmingham, England, a British company Filed Sept. 28, 1964, Ser. No. 399,752 8 Claims. (Cl. 3742) ABSTRACT OF THE DISCLOSURE An oblique angle type snow plough comprises a. frame pivoted on a propelling vehicle for angular movement between raised and lowered positions. A blade structure carried by the frame remote from the pivot includes a blade that is disposed at an angle to the longitudinal axis of the vehicle and which in the lowered position of the frame has its lower edge substantially horizontal with the opposite ends of the blade at unequal distances from the pivot axis. The blade structure is so tiltably mounted about a longitudinal axis on the frame, and cooperating abutments are so provided on both the frame and blade structure that as the frame is raised the blade structure is twisted to preserve the horizontal disposition of the lower edge of the blade. This insures that the rearmost end of the blade will be raised sufiiciently to be clear of the road for transportation when the frame is raised.

This invention relates to snow ploughs of the kind wherein a substantially straight snow plough blade can be set at an angle to the longitudinal axis of a propelling vehicle on which it is adapted to be mounted through an intermediate frame pivotally mounted on the vehicle, so that by raising the end of the frame remote from the vehicle, the plough blade can be lifted clear of the road for transportation in an inoperative position.

Plough blades of the aforesaid kind are commonly known as angle-type blades as distinct from the also common V-type blades, and are mounted at an angle other than a right angle to the longitudinal axis of the propelling vehicle with the result that when the frame is turned to raise the plough blade structure, the two ends of the blade are lifted to different heights due to the different distances of the said ends from the axis of rotation of the frame on the vehicle.

The present invention has for its principal object a snow plough incorporating means for preserving a substantially level position of the plough blade when its supporting frame is raised.

The invention consists of a snow plough comprising an angle type plough blade structure mounted on a frame adapted for pivotal connection to a propelling vehicle, characterised by the provision in the mounting of the blade structure on the frame for relative twisting movement therebetween, and abutments provided on the blade structure and frame which abutments coact to twist the blade structure relative to the frame as the blade structure and frame are raised, so as to preserve a substantially horizontal position of the blade.

One example of the practical realisation of the invention is described with reference to the accompanying drawings, wherein:

FIGURE 1 is a plan view of a plough according to the invention mounted on a propelling vehicle; and

FIGURE 2 is a fragmentary perspective view on an enlarged scale showing the connection of the frame to the plough blade structure of FIGURE 1.

Referring initially to FIGURE 1, the snow plough comprises an angle type plough blade structure 5 comprising a blade proper 3 articulated by links 4 to vertical cross pieces 6 interconnecting the ends of a pair of horizontally extending upper and lower members 7 and 8 and carrying castor wheels 2. By virtue of the links 4 the blade 3 is able to rise relative to the members 7 and 8, for example, to enable the blade to glance over an obstruction. The members 7 and 8 have a pair of vertically aligned holes as hereinafter more particularly described which accept a vertical swivel pin 9 also extending through and detachable from a sleeve 16 fastened to the apex of an A-shaped frame 10 having feet pivotally connected at 11 to the front of the propelling vehicle 12. Extending rearwardly one from each side of the blade structure 5 is a pair of arms 13 which can be located by pin and opening means 21 in any one of a number of selected positions about the axis of pin 9 relative to the A-frame 10 so as to set the blade structure 5 at a selected angle relative to the longitudinal axis of the propelling vehicle. A fluid-operated ram 14 connects the propelling vehicle to the vicinity of the apex of the A-frame 10 to efiect raising and lowering of the frame 10 and the blade structure 5.

Referring now to FIGURE 2, whilst the hole (not seen) in the lower member 8 is a substantially close fit about the swivel pin 9, the hole 15 in the upper cross member 7 is elongated approximately three to four times the diameter of the swivel pin 9 in the direction of the length of the blade 3 to permit twisting movement of the blade structure 5 in a vertical plane relative to the swivel pin 9. Further, the height of the swivel pin sleeve 16 is substantially shorter than the gap between the two members 7 and 8 between which it is disposed.

Welded to the A-fra1ne adjacent its apex is an upstanding bridge 17 carrying a pair of abutment pieces 1!? located one on each side of the swivel pin sleeve 16. The height of the abutment pieces 15? relative to the top of the swivel pin sleeve 16 and the underside of the upper member 7 is such that with the A-frame 19 and plough blade 3 lowered to their normal working positions with the former resting on the lower member 8, the abutments 19 are spaced beneath the underside of the member 7 so as not to interfere with relatively small twisting movements of the blade structure relative to the A-frame. However, as the A-fra'me 1G is raised about its trunnions 11 by the ram 14 to raise the blade 3 to an inoperative position, so the swivel pin sleeve 16 moves up the swivel pin 9 until one or other of the abutment pieces 19, according to the angle of blade 3, contacts a second abutment in the form of the underside of the member 7. With continuing raising of the A-frame these abutments serve to turn the blade structure 5 in a vertical plane as permitted by further movement of the swivel pin 9 in the elongated slot 15. By this means the upper member 7 can come to rest in a substantially horizontal position across the first abutment piece and the top of the swivel pin sleeve 16.

Preferably, the tops of the abutment pieces 19 are formed as ramps 20, both inclined rearwardly and upwardly, so that as the blade 3 is swung horizontally between a pair of equal but opposite alternative angular positions one on each side of the longitudinal axis of the A-frame, so the upper member 7 rides down one ramp 20 and up the other whilst rocking on the top of the swivel pin 16, so as to preserve a substantially horizontal position of the blade structure 5 to avoid fouling of an end of the blade 3 with the ground and preserving the balance of the blade.

I claim:

1. An angle type snow plough comprising an angle type plough blade structure, a frame adapted for pivotal connection to a propelling vehicle, means mounting said blade structure on the frame with provision for relative twisting movement therebetween comprising a swivel pin mounted in a vertical sleeve integral with the frame, said pin extending through a substantially close fitting hole and through an elongated hole in a pair of vertically spaced members forming'a'part of the blade structure, and cooperating abutments on said blade structure and frame coacting to twist the blade structure relative to the frame as the blade structure and frame are raised, so, as to preserve a substantially horizontal position of the blade edge.

2. A snow plough according to claim 1, wherein said abutments comprise at least one first abutment on said rame laterally offset to the swivel pin, and a complementary second abutment in the form of a horizontflly extending member rigid with the blade structure, said horizontally extending member being the upper of said pair of vertically spaced members.

3. A snow plough according to claim 2, wherein two firstabutments are mounted on said frame one on each side of the swivel pin.

4. A snow plough according to claim 3, wherein the tops of said first abutments are formed as ramps.

5. A snow plough according to claim 1, wherein said sleeve is shorter'than the gap between said vertically spaced members and is a sliding fit about said swivel pin to permit limited twisting movement of the blade structure relative to the frame without contact between said abutments.

6. An oblique angle type snow plough comprising a frame adapted for pivotal connection to a propelling vehicle .for angular movement between raised and lowered positions, a plough blade structure, including a blade having a substantially straight lower edge disposed at an oblique angle with respect to the direction it is moved by theovehicle mounted on said frame remote from said pivotal connection with provision for relative twisting movement between the blade structure and said frame about a substantially horizontal axis perpendicular to the general plane of the blade, the blade structure being mounted so that when the frame is in the lowered position said lower edge of the blade is substantially horizontal and V the two ends of the blade have unequal spacing from the axis of the pivotal connection of the frame to the vehicle, and complementary abutments on said blade structure and frame, said abutments coacting when said frame is raised to positively twist the blade structure relative to said frame so as to preserve the substantially horizontal disposition of the lower edge of said blade during raising of the frame, thereby to counteract a tendency of the lower edge of the blade to assume a non-horizontal disposition during raising. 1

'7. An angle type snow plough comprising a frame adapted for pivotal connection to a propelling vehicle, a plough blade arranged at an angle to an axis extending longitudinally of said vehicle, means for swinging said frame about said pivotal connection for raising or lowering said blade, and means mounting said blade on the frame forwardly of said pivotal connection for tilting the blade substantially in its plane as the frame is raised whereby to raise the rear end loweredge of said blade correspondingly with the forward end of said lower edge. 8. The snow plough defined in claim '7 wherein said means for mounting the blade on the frame includes a generally vertical pivot, and means is provided for adjusting the blade about said pivot for varying the angle of said blade relative to said axis. 2

References Cited UNITED STATES PATENTS 7 1,961,011 5/1934 Pearson 37 X 2,095,096 10/1937 Humphrey 37-4-2 2,264,368 12/1941 Gettelman 37-42 3,012,345 12/1961 Krueger 37 42 v FOREIGN PATENTS 826,662 1/ 1960 Great Britain.

ABRAHAM G. STONE, Primary Examiner.

R. L. HOLLISTER, Assistant Examiner. 

